Tube Rolling w/Crack

[(312)]

Hence my skepticism on it's authenticity.

Thanks PB for confirmation.

Not only functional, but quite a pleasant listen as well.

 

[Paul Birkeland]

Hence my skepticism on it's authenticity.

I have never, ever, ever seen a faked 6080. 

 

[Doc B]

Me either, but I do have a really rare miniaturized 6080.

 

[(312)]

Maybe authenticity was a poor choice of a word. I was more curious of the possibility of a rebrand.
Knowledge gained though. Thanks.

 

[Paul Birkeland]

The problem is that the other tubes that would look convincingly like a Sylvania 6080 are going to be RCA, Tung Sol, etc.  It wouldn't make sense to take a $10 tube and spend the time relabeling it to look like a different $10 tube.

 

[(312)]

Point taken. I just couldn't find another, photo wise, that matched mine with the fabric at the base, dimple getters and different font. Just trying to get educated.
I appreciate your time.

 

[attmci]

You need a tire I or II power tube recommended here:

https://forum.bottlehead.com/index.php?topic=663.465

 

[attmci]

Hi I'm new here been into audio hobby since my twenties. Started with solid state until I got my first tube amp. Recently I bought a fully loaded Crack and am loving it. I'm wondering about philips 7316 on price of $390. I won't spend that kinda money on small tube unless it really performs.

I wish I could use my Baldwin 12ax7 but I guess it requires more voltage then the Crack provides? Currently running a Baldwin 12au7 and rca 6as7g. I'm seeing if I like my Bendix 6080wb that's very euphonic vs rca which produces more bass slam.

I know $$ is not a problem for you because you own WA33, Abyss 1266 and many other toys. But this is not worth the advised price.

https://www.ebay.com/itm/HP-By-Amperex-7316-ECC186-12AU7-ECC82-NOS-NIB-Super-Rare-/164290809752

 

[attmci]

https://www.ebay.com/itm/274653765201?mkevt=1&mkcid=1&mkrid=711-53200-19255-0&campid=5338722076&toolid=10001

 

[Mucker]

So, I built my Crack +SB in 2014 and it's always in play with my Technics SL-1200 turntables. I recently started revisiting the Bottlehead forum after experiencing some noise (hum and buzz) and wanted to see if I could eliminate it. I ended up re-flowing all the connections and added the ground diodes. I also cleaned up some of the wire runs and shortened wires where I could.

What I discovered is that the I could achieve dead silent amplifier operation when a Chatham 6080WA and and various Tung-Sol 12AU7's were installed.

The same 6080 and one of my Channel Master 6SN7GTB's produced the same dead silence.

What gave me noise was a Chatham 2399 and various 6SN7GT's (hum and buzzing). Other than the Channel Master tubes (which are excellent!), all of the 6SN7GT's (VT-231's) experienced some humming no matter what I tried to fix.

I am guessing the noisy tubes I have are less than perfect. I have a couple of pair of RCA 6AS7G's that sound great but the glass (or other) vibrates into high pitched noise. It can be eliminated with much pressure on the tube but I know that dampeners can kill the audio. It's not so annoying for listening but is clearly audible in between tracks.

Back to the Channel Master 6SN7GTB, I was able to acquire 3 of these Mullard made (Japan) tubes for $20 per tube recently and they are outstanding. I'm not sure if they are better than the Tung-Sol 12AU7 but they are at least the equivalent. I need more time with them. I bought a 6SN7 adapter from Garage 1217 and it's very nice quality. I wanted to guard the exposed solder pads and came up with a simple plastic removable sleeve. It's actually made from just a $1 sink drain pipe from home depot. It fits perfectly and looks like it's part of the tube when placed over it. Anyway, this amplifier is just amazing in performance and simplicity (and superb electrical engineering!) It's so good I am wondering if a Crackatwoa is worth upgrading to. Or an S3X for my HE-6se and Grados (I use SS amps for them).

 

[TubeGuy12]

I bought a 6SN7 adapter from Garage 1217 and it's very nice quality. I wanted to guard the exposed solder pads and came up with a simple plastic removable sleeve. It's actually made from just a $1 sink drain pipe from home depot. It fits perfectly and looks like it's part of the tube when placed over it. Anyway, this amplifier is just amazing in performance and simplicity (and superb electrical engineering!)

Nice job on that G1217 adapter cover, Mucker. I've been concerned with the proximity of those solder pins to the volume knob, too. I initially thought of simply putting a couple large diameter nitrile o-rings on the pins. I discovered that the problem with that candidate solution is that some nitrile is made with carbon. And carbon could create a quasi-resistor, which in turn might allow a tiny bit of current to move across the o-ring. Your solution is much better. I'm going to do what you did (1.25" diameter plastic pipe). So, thanks for posting those photos.

 

[Mucker]

Glad it can help you. I was thinking of going without but this was dead simple, plays the part, and does its' job ....

 

[Knightstick]

Will a 6AS7G/6520 tube work in the Crack? Just curious as to how the tube rolling works?. I saw the tube equivalents post but not sure how it all works as I saw this tube but there was no mention of a 6520 tube. It mentioned nothing about being a power tube though. Is this the defining word I'm missing?

 

[Larpy]

A 6AS7 will work just fine.  The 6080 tube (usually shipped as stock) is a ruggedized version of the 6AS7.  Electrically, they are the same.

You can also use a 5998 or 7236 (which is a computer rated 5998), though they are harder to find these days.

I'm not familiar with the 6520 tube, though it's often included in the 6AS7 "family."  Presumably it will work, though I'll defer to those who know more about this tube than I do.

 

[Knightstick]

Thank you very much sir.

 

[Paul Joppa]

6520 has better balanced sections, and a few other inprovements to reduce drift of characteristics as it ages. Neither is especially important in Crackbecause of the circuit (cathode follower) and the relatively low dissipation.

 

[cddc]

Will a 6AS7G/6520 tube work in the Crack? Just curious as to how the tube rolling works?. I saw the tube equivalents post but not sure how it all works as I saw this tube but there was no mention of a 6520 tube. It mentioned nothing about being a power tube though. Is this the defining word I'm missing?

6AS7G is basically the same as 6080, just in a different glass envelope, so definitely works perfectly fine in Crack.

6520 is a "premium 6AS7G", but it is essentially either a Tung Sol/Chatham 6AS7G or a 5998. So definitely works perfectly in Crack as well.

 

[Colonl_Charisma]

I've been using a 6SN7GT as my input tube (using an adapter in my Crack), and I was wondering if anyone has recommendations for another input tube. I love the 6SN7GT, but I've found that they can be a bit noisy. I've tried a few 12AU7 tubes, but I do not like the way they sound in my Crack. To my ears, they seem to lack in gain and soundstage.

 

[2wo]

Have you thought about the 6FQ7? I think you need an adapter or rewire the socket...John

 

[Colonl_Charisma]

I’ve never come across that type of tube, John. I’ll look into it. What kind do you have, and what aspects of it do you enjoy?